To enhance an operator's driving experience and a vehicle's performance and safety, various electronic enhancements and systems assist or replicate automotive systems that were previously mechanical in nature. One such automotive system is the brake-by-wire system. In a brake-by-wire system, an operator's activation of the brake pedal is determined by one or more sensors. Data from the sensors is then used by a computer or processor to determine an appropriate braking force to apply to the brakes.
Several different types of brake-by-wire systems exist. For example, in an electro-hydraulic braking system, the computer commands an electro-hydraulic actuator to apply hydraulic pressure to the brake calipers to stop the vehicle. In contrast, in an electromechanical braking system, the braking force is applied instead by an electronic caliper which utilizes a small motor to push the brake pads against the rotor to stop the vehicle. Additionally, vehicles can incorporate combined systems such as electro-mechanical and electro-hydraulic systems. Also, hybrid cars can utilize a combination of friction braking, which can be electromechanical or electro-hydraulic, and regenerative braking, which is also a type of electronic braking in which speed is reduced by converting kinetic energy into electrical energy.
Regardless of the particular type of braking system, an important feature of many braking systems is the ability to be appropriately commanded during panic braking situations. In a panic braking situation, the vehicle operator typically applies force to the brake pedal at a very rapid rate, but not necessarily with a large enough force to decelerate the vehicle fast enough, based on the force alone. A braking control system can apply an appropriate level of braking during such a panic braking event, for example using a panic braking command algorithm. However, panic braking algorithms and systems that provide the driver of the vehicle with an optimal level of control of braking during a panic braking event, and/or do not require a lag time before applying an appropriate increased level of braking, are needed. In the future new government regulations may impose specific requirements for panic braking algorithms and systems. For example, new proposed regulations in the European Community would require that panic braking assist algorithms and systems provide braking torque that is at least double the braking torque that would ordinarily be represented by the driver's brake request during a panic braking event. Accordingly, panic braking algorithms and systems that will meet future governmental regulations also are needed.
Accordingly, it is desirable to provide an improved method and system for controlling braking during a panic braking event that provides the driver with more braking control during the panic braking event. It is also desirable to provide a method and system for controlling braking during a panic braking event that decreases or eliminates lag time before applying an increased level of braking. In addition, it is desirable to provide a method and system for controlling braking during a panic braking event that more easily meets future governmental regulations. Furthermore, other desirable features and characteristics of the present invention will be apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background.